Soviet Five-Pointed Rotary Is the Final Boss of Wankel Engines

Rotary engines have almost completely gone out of production, but they're still beloved by enthusiasts. Eschewing pistons for a spinning three-sided rotor, they rev to the moon and sound great doing so. Most powerful rotaries are usually just a bunch of these three-sided rotors mated together, but one Russian design that caught our eye does away with multiple rotors, opting instead for a single five-sided rotor with four combustion chambers. We've never seen anything like it.

There's not a lot of information available about this engine. Most of what we know is the same basic facts repeated over and over again. It was allegedly designed to propel a Soviet-era torpedo and was fueled by hydrogen peroxide as opposed to conventional fuel like gasoline, kerosene, or diesel. No air for combustion underwater, of course. Output was reportedly 730kW, or about 979 horsepower. Beyond that, the trail gets pretty cold.